Syrian regime forces on Wednesday escalated its air raids on eastern Damascus in an attempt to break the blockade imposed by the opposition factions on the "Military Vehicles Administration,” which is likely to include between 200 and 300 elements of the regime. While factions urged these elements to surrender, there was information about the readiness of government forces to launch an assault to break the siege and capture 11 regime fighters. The Syrian regime forces backed by Russian jets escalated bombing of the last rebel bastion on the eastern outskirts of Damascus as they prepared to break a siege of an army base encircled by opposition forces, residents and witnesses said on Wednesday, according to Reuters. Reuters said the “army was amassing elite forces to prepare for a major assault on the Military Vehicles Administration, which is besieged by rebels. At least 200 troops were believed to be trapped within its sprawling, heavily defended grounds.” In conjunction with the regimes preparations to carry out a major military operation in the region, opposition factions on Wednesday called on besieged government forces in the "vehicle administration" to surrender. “The front lines of Ghouta are witnessing battles and clashes and big losses inflicted on Head of Syrian regime Bashar al-Assad’s forces and his militias,” said Hamza Biriqdar, the spokesman for Jaish al Islam, a main rebel faction. Shaam news announced that “the rebels managed yesterday to detain 11 elements of the Assad forces during the battles in the city of Harasta and the Vehicles Administration,” pointing out that “a video was posted showing the captured soldiers who were taken to be used in the swap process,” according to what they announced in the video. An opposition source confirmed to Asharq Al-Awsat that 11 elements were detained, including officers, noting that clashes were ongoing in Harasta and Arbin and that the rebels were besieged from all the directions of the Vehicles Administration. Civil defense sources said that in four days of heavy aerial strikes since Friday, 38 civilians have been killed and at least 147 people have been injured. Five civilians were killed on Tuesday, Reuters reported. Residents said at least 30 aerial strikes hit residential areas of Eastern Ghouta on Tuesday. Shelling of a market in the city of Douma, the main urban center in the Ghouta, left one dead and scores injured.